ABSTRACT

The variation of zeta potential of high ash Indian coals in the presence of various surface modifying conditions has rarely been studied in depth. The objective of the present investigation was to perform a detailed comparative study on surface zeta potential of two distinct Indian coals that have substantial differences in their ash content and surface chemistry. Detailed characterization studies of the two coals were performed using FTIR, petrography, and proximate and ultimate analyses, which demonstrated that Topa coal was more hydrophobic in comparison to Kulda coal. Electrokinetic measurements at ambient temperatures demonstrated that the zeta potential of both coals was dependent on pH, ionic strength, and type of surfactant. The surface potential of both coals, irrespective of the extent of mineral association, was only affected by cationic surfactant over a prolonged contact time. XRD analysis of the coal ash samples revealed the presence of quartz, hematite, mica, and zeolite as the predominant minerals. In the present study, the inherent and surface chemistry of mineral-rich coals was correlated through the measurements of zeta potential. It was concluded that the variation in mineral matter content does not impact the zeta potential of coal particles significantly.

摘要

很少有人深入研究高灰分印度煤在各种表面改性条件下的 zeta 电位变化。本调查的目的是对两种不同的印度煤的表面 zeta 电位进行详细的比较研究，这两种煤在灰分含量和表面化学方面存在显着差异。使用 FTIR、岩相学以及近似和最终分析对这两种煤进行了详细的表征研究，结果表明与 Kulda 煤相比，Topa 煤的疏水性更强。环境温度下的电动测量表明，两种煤的 zeta 电位都取决于 pH 值、离子强度和表面活性剂的类型。两种煤的表面电势，无论矿物组合的程度如何，仅在延长的接触时间内受阳离子表面活性剂的影响。煤灰样品的 XRD 分析显示石英、赤铁矿、云母和沸石是主要矿物。在本研究中，通过测量 zeta 电位，将富含矿物质的煤的固有化学和表面化学联系起来。得出的结论是，矿物质含量的变化不会显着影响煤颗粒的 zeta 电位。